Main functions of the IPv6 switch Center

We have mentioned the IPv6 exchange center in some articles. Now, let's summarize the main functional aspects of the IPv6 Exchange Center. There are five major content connection problems, routing addresses, interactive traffic, management, and design.

Primary function 1 of the IPv6 switch center: Network Connection

The switch center basically adopts L2 switching. In the early days, most of them adopted ATM switches, and Ethernet switches are basically used. This is especially true when Ethernet has grown to 10 Gbit/s interface level ｡

Two schemes can be used to connect the carrier router. First, the operator places the router directly in the switch center, so that the management interface is very clear, the exchange center only provides information exchange channels with other carriers. Another solution is to set up some routers in the Exchange Center. Each carrier connects to these routers through links, for Policy Routing and forwarding ｡

The two solutions have their own advantages and disadvantages. The former has a clear management interface, but may be a little wasteful in cost. The latter, however, saves a little, however, the management interface is not clear enough. The specific implementation can be adjusted and implemented according to the specific policies of operators ｡

From the perspective of the construction of the switch center, the so-called LAN-SP router is set in the switch center; the WAN-SP router is not in the switch center, but in the SP's own data center; and the distinction between hybrid methods-both of the above two cases are involved. In fact, there is no specific difference in technology, mainly the arrangement of the connection links from the SP to the switch center, and the location of the device ｡

The selection of specific devices determines the switching capacity, port quantity and speed based on traffic prediction, number of access SP, and other factors, as well as other additional functions, for example, speed limit, service quality guarantee, and advanced traffic statistics functions ｡

IPv6 switch center's main function 2: SP router device Address Configuration

Because the routers of carriers in the exchange center use different IPv6 address blocks, and from the management perspective, they do not want to use the IPv6 address of the other party when connecting with other SP, there are several solutions to use IPv6 addresses fairly and perform peer-to-peer configuration, mainly including the following methods:

◆ Use the local link address. Each SP uses the local link address, which is fair and does not interfere with each other ｡

◆ Use an aggregated global unicast address registered in the IPv6 Exchange Center. By applying for an independent IPv6 address from the RIR exchange center, such as/48 and 64/prefix, so that each IPv6SP can establish a peering relationship ｡

◆ Shared prefix. Each SP shares the prefix. Especially when the switch center cannot provide IPv6SP with IPv6 connectivity or can aggregate the global unicast prefix ｡

Main function 3 of the IPv6 switch center: routing Interaction

As mentioned above, the SP router in the IPv6 exchange center performs route interaction through BGP4 +, because route interaction requires TCP connection maintenance, if the exchange center accesses a large number of SP routers, there may be a large amount of maintenance. Meanwhile, the number of peer-to-peer sessions on the router may also be limited, generally, the Routing Server is introduced in the switch center ｡

The Routing Server (RS) is used to exchange routes between the SP connected to the NAP. The specific implementation is to collect route information of each SP and process the information according to the SP routing policy, finally, the processed route information is transmitted to each SP router. RS uses BGP4 + as the Inter-Domain Routing Protocol to interact with the SP router connected to the NAP ｡

RS does not forward data packets between the SP connected to the NAP. In fact, it uses the BGP third-party routing information capability to transmit route information from one SP to another, and direct the Next Hop to the SP router of RS, communication traffic is actually directly exchanged on the SP router ｡

A key role of RS is to reduce the number of BGP4 + peering session routers. In NAP, BGP4 + peering sessions need to be maintained. This can reduce the load, in the exchange center, each SP maintains a peering session with RS, rather than maintaining multiple sessions with other SP directly. In large NAP, RS service is critical, this is because the number of BGP4 + peering sessions supported by the router is limited ｡

Another purpose of RS is to ensure the security of routing information. RS provides an advanced tool to manage route information changes between SPs and filter out invalid data in the information, or RS implements policy routing according to the pre-defined rules of SP ｡

IPv6 switch center's main function 4: Traffic Management Issues

You can directly establish a point-to-point connection to the vro of the exchange center. You can divide the vrovlan through VLAN and implement bandwidth control through traffic control and other measures, and other measures to support service quality ｡

The interconnection between networks of multiple operators can be achieved through multiple VLANs, so the traffic model is complicated. It is a unified traffic/bandwidth limit for all the SPs, or is there a bandwidth limit for each SP?

Using an ATM switch, you can use PVC for more precise traffic control and analysis. However, Ethernet switches are somewhat lacking from the current perspective ｡

IPv6 switch center's main function 5: Reliability Design

The key role of NAP in network interconnection is obvious. In order to ensure the high reliable operation of the exchange center, a high reliability design should be adopted, especially in the aspect of core exchange ｡